On Sat, 10 Nov 2001 01:53:08 -0500, Redbeard wrote:
> I could also take one of the higher res. whole earth pictures I've found and
> just cut out the US.  But the problem with that is two-fold.  1) too *low*
> resolution.  2) improper projection for a decent rendering of US (although I
> could cut from a mapped spherical isosurface)

What about ETOPO2 (2-minute gridded elevation) or ETOPO5 (5-minute)?

A minute of latitude is about a mile (at the US' latitude, a minute of 
longitude is about 3/4 mile) so the 2-minute data for the US wouldn't be all
that huge (4000x2000?), but probably big enough for a decent-sized image.  
The projection might be a problem, but that's a Simple Matter Of Programming.
If it really is a gridded dataset, plotting it directly will result in 
something that looks like a Mercator projection that's been squished 
vertically somewhat.

-- 
#macro R(L P)sphere{L F}cylinder{L P F}#end#macro P(V)merge{R(z+a z)R(-z a-z)R(a
-z-z-z a+z)torus{1F clipped_by{plane{a 0}}}translate V}#end#macro Z(a F T)merge{
P(z+a)P(z-a)R(-z-z-x a)pigment{rgbt 1}hollow interior{media{emission T}}finish{
reflection.1}}#end Z(-x-x.2y)Z(-x-x.4x)camera{location z*-10rotate x*90}

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